He went on: "This is a hard job, and I'm not just saying this to win favour with lorry drivers. It's a hard job - change gear, change gear, change gear, check your mirrors, murder a prostitute, change gear, change gear, murder. That's a lot of effort in a day."

Top Gear producers plan to transmit other Morse code message during this week's show, including "I Voted For Ross Perot", a reference to the US billionaire who twice stood for president, according to The Sun.

"It's all just a bit of fun. Top Gear is known for being irreverent so this is just the producers' idea of a joke," the newspaper quoted a BBC insider as saying.